Consumers want portable electronic devices that display alphanumeric and graphical messages in the proper position regardless of the orientation of the electronic device. These electronic devices include compact disc players, two-way radios, cellular telephones, computers, and similar devices. To show graphical images and alphanumeric messages, such devices typically have a virtual image display although other types of displays may be used.
In use, the display projects an image in a fixed orientation relative to the electronic device. For example, the top of the image is oriented usually with the top of the device. To see the image properly, a user must hold the electronic device in the proper position. The electronic device is limited to uses related generally to the fixed position of the image. Of course, other uses are possible if the user wants to view an image upside down, sideways, or other awkward position. Generally, this scenario is not the case. Consequently, there is a problem when a user wants to use an electronic device in a position for which the display was not designed to project the image.
Many cellular telephones are designed for hands-on use with the image having the same orientation as the phone--top of the image oriented with the top of the phone. When used hands-free, the hands-on phone may be inverted for use such as when it is clipped to the visor of an automobile. In this situation, the display image would be appear upside down to the user.
In the prior art, a virtual image display is mounted tangentially to an electronic device. The image can be viewed properly with the electronic device in only one position. The user must hold the electronic device with the virtual image display in front of the proper eye. If the user switches the electronic device to the other eye, the image will appear upside down and backwards. If the user views the electronic device from the top such as when it is held on a belt, the image will appear sideways. Hence, there is a need for an electronic device with an auto-positioning virtual image display.
In addition, the image controls need to operate in relation to the changing orientation of the image. In a device with a fixed-orientation image, the image controls operate in a fixed relation to the orientation of the image. For example, some displays include a switch to scroll through a message. To scroll in a particular direction, the user moves the switch in the same direction. The user moves the switch toward the top of the display to scroll toward the top of the image. This design works because the image has a fixed orientation. However, this design would not work appropriately if the orientation of the image changes. If the orientation of the image is 90 degrees different from the display orientation, then the inputs from the imagine controls need to rotate by the same 90 degrees in order to work properly with the image. In this example, if the image controls did not rotate to the same degree as the image orientation, then moving the scrolling switch toward the top of the display would cause the image to scroll sideways.
Accordingly, there is a need for an electronic device with an auto-positioning virtual image display in which the image controls operate in relation to the changing orientation of the image.